Humidity responsive device



l Sept 17, 1935. F. s. MARCELLUS 2,014,943 I HUMIDITY RESPONSIVE DEVICE Filed March 31, 1952 f Inventor: Ffedricm S .Narceliu His Attorney.

Patented Sept. 17, 1935 UNITED STATES PATENT oFFlcE HUMDITY RESPUNSIVE DEVICE Fredrick S. Marcellus, Scotia, N. Y., assigner to General LElectric Company, a corporation of New York Application March 31, 1932, Serial No.I 602,182

My invention relates to humidity responsive the side walls are made cylindrical and the upper devices .and has for its principal object the proportion is closed by means of a plug I4 having an In accordance with my invention in its pre- If desired, a shield I formed, for example, by ferred form, a bulb or cup composed of wood, pressing from perforated sheet material may be papier-mch, or other fibrous or relatively rigid utilized to protect the bulb II .against crushing l0 material is provided with an opening to which impacts or puncture. The tube I2 may be fasthe Walls of the bulb absorb or give off moisture an .independent support for the bulb II may, if 15 causing variations in the quantity of liquid which jecting the material to strains or the apparatus is contained in the tube. Suitable means such to changes in calibration in case the device is as a scale paralleling the tube maybe provided suddenly moved from place to place.

for measuring the quantity of liquid therein to A quantity of liquid, preferably one such as 20 trolled by lthe position of the liquid within the tube placed Within the bulb I I so as to partly lill the in response to variations in humidity. tube I2. If desired, a screw I8 threaded through 25 'I'he features of my invention which I believe to the plug I 4 so as to extend slightly into the mass be novel and patentable will be pointed out in of liquid I 1 may be provided in order to make the claims appended hereto. My invention itself, minor adjustments in the quantity of liquid rehowever, will be best understood by referring to mailling in the tube I2 thereby adjusting the Zero t e following description taken in connection of the device. The level I9 of the liquid in tube 30 of the embodiment shown in Fig. 1; and Fig. 3 is to close the upper end of the tube I2 against DOS- a cross-sectional view of a portion of a modied sible spillage of the liquid l1 without entirely cut- 35 apparatus of the type shown in Fig. 1. ting o the access of air pressure to the portion Referring now more 1n detail to the drawing in 0f the tube I 2 above the level I9 of the liquid I1 which like reference characters refer to like parts If a Conducting hqllld Slleh 8S mercury 1S 11111- throughout, I providea bulb or cup II communilZed t0 ll the CUD and tube l2. the device eating with a tube I2 supported by a backing may be utilized to control electrical circuits in 40 member I3. The cup II may be composed of response to variations in humidity by providing materials having the property of expanding and inthe tube l2," In the apparatus illustrated I contracting with variations in moisture content have shOWn an adjustable electrode 22 in the and preferably relatively rigid for the sakev of form of a rod or wire passing through a. hole in 45 operation of my 45 -I said tube varying cup II and is connected to the second binding post 26 is provided so that an electrical circuit from binding post 24 to 26 is closed when the level I! of the mercury I1 rises to the lower end of the rod 22. Any desired apparatus such as remote indicating or humidity correcting apparatus may be controlled by means of suitable electrical ap-4 paratus (not shown) having leads connected to the binding posts 24' and 26.'

Ii a relatively costly liquidv such as mercury is employed, I may, if desired, further reduce the cost of my device by filling the greater portion of the inner cavity of the bulb II with a body 21, as shown in Fig. 3, conforming substantially to the shape of the cavity in the bulb I I but slightly smaller so as to leave only a small space for the liquid I1, thereby greatly reducing the quantity of liquid required. In order to permit free passage of liquid I1 between the bulb I I and tube I2, and, if desired, to permit the tube I2 to extend intoA the inner portion of bulb II, a portion 2B of the body 21 is cut away. Since the body 21 is surrounded by mercury and is furthermore wholly enclosed, it will not be subjected to variations in moisture and consequently it may be composed o! wood, glass, porcelain, or any other desired material without regard to its hygrometric properties,

In accordance with the provisions of the patent statutes I have described the principle of invention together with the apparatus which I now consider to represent the best embodiment thereof, but I desire to have it understood that the apparatus shown is only illusl ttative and that the invention may be carried out by other means.

What I claim as new and desire to secure by Letters Patent of the United States, is: i. A humidity responsive device comprising a Jlooden bulb expansible and contractible with vanationsin humidity, a closure therefor having an opening therein, a tube joined to said opening, md a quantity of mercury contained in said bulb and said tube, the relative quantity of mercury in with variations in humidity. 2. A humidity responsive device comprising a hollow wooden body expansible and contractible with variations in humidity and having an opening therein, a tube connected to said body at said opening, and a quantity of liquid contained in said hollow body and said tube, the relative quantity of liquid in said tube varying with variations in humidity.

3. A humidity responsive device comprising a rigid bulbl composed of fibrous material expansible and contractible with variations in humidity and having an opening therein, a tube connected to lsaid bulb at said opening, a quantity of liquid filling said bulb and a portion of said tube, said portion varying with variations in humidity.

4. A humidity responsive device comprising a rigid bulb composed of a material expansible and contractible with variations in moisture content, a relatively non-expansible tube connected to said bulb, and a quantity of liquid contained in said bulb and being transferred to and from said tube in response to variations in humidity 5. A humidity responsive device comprising a cup which comprises a fibrous material expansible and contractible with variations in moisture content, a body contained within said cup and conforming substantially to the shape of the space within said cup but smaller than said space, a relatively non-expansible tube connected to the interior of said cup, a liquid occupying the free space in said cup and a portion of said tube, the portion of said tube occupied by said liquid varying with humidity.

6. In a humidity responsive device, a hollow wooden body expansible -and contractible .with variations in humidity and having an opening therein adapted to receive a tube, and a quantity of liquid contained in said hollow body.

7. In a humidity responsive device, the combination of a rgid bulb composed of fibrousvmaterial expansible and contractible with variations in humidity and having an opening therein, and a quantity of liquid filling said bulb and being partially ejected from and retracted into said bulb in response to variations in humidity.

FREDRICK S. MARCELLUS.

said tube, a portion of said liquid csf 

